TEMPORAL AND SPATIOTEMPORAL VIBROTACTILE DISPLAYS FOR VOICE FUNDAMENTAL-FREQUENCY - AN INITIAL EVALUATION OF A NEW VIBROTACTILE SPEECH-PERCEPTION AID WITH NORMAL-HEARING AND HEARING-IMPAIRED INDIVIDUALS

Four experiments were performed to evaluate a new wearable vibrotactil e speech perception aid that extracts fundamental frequency (F0) and d isplays the extracted F0 as a single-channel temporal or an eight-chan nel spatio-temporal stimulus. Specifically, we investigated the percep tion of intonation (i.e., question versus statement) and emphatic stre ss (i.e., stress on the first, second, or third word) under Visual-Alo ne (VA); Visual-Tactile (VT), and Tactile-Alone (TA) conditions and co mpared performance using the temporal and spatio-temporal vibrotactile display. Subjects were adults with normal hearing in experiments I-II I and adults with severe to profound hearing impairments in experiment IV. Both versions of the vibrotactile speech perception aid successfu lly conveyed intonation. Vibrotactile stress information was successfu lly conveyed, but vibrotactile stress information did not enhance perf ormance in VT conditions beyond performance in VA conditions. In exper iment III, which involved only intonation identification, a reliable a dvantage for the spatio-temporal display was obtained. Differences bet ween subject groups were obtained for intonation identification, with more accurate VT performance by those with normal hearing. Possible ef fects of long-term hearing status are discussed. (C) 1998 Acoustical S ociety of America. [S0001-4966(98)03010-0].